Vulcanizing and stretching press



March 28, 1939. c. F. scHNucK VULCANIZING AND STRETCHING PRESS Filed Oct. 25, 1937 s Sheet-Sheet 1' Y 7 90 4 ATTORNEYS- March 28,1939.

C. F. SCHNUCK VULCANIZING AND STRETCHING PRESS s Sheets-Sheet 2 Filed Oct. 25, 1937 INVENTOR ATTORNEYS.

Marcli 28; 1939. c. F. SCHNUCK VULCANIZING AND STRETCHING PRESS Filed Oct; 25, 1937 3 Sheets-Sheet 3 BY 2 74 I ay! v M ATTORNEYS;

Patented Mar. 28, 1939 VULCANIZING AND STRETCHING PRESS Carl F. Schnuck, New Haven, Conn, assignor to Farrel-Birmingham Company, Ansonia, Conn., a corporation of Connecticut Application October 25,

9 Claims.

This invention relates to presses of that general type wherein a relatively thin sheetlike piece of material may be compressed, and heated if desired, while it is under a tensile stress and more 6 particularly to machines of this character which are adapted simultaneously to stretch and com.- press several such sheets in that manner.

The principal object of the invention is to provide a press having a plurality of platens, including upper, intermediate and lower ones, between which sheets of material may be interposed, with a stretching frame, and a clamping frame, for each adjacent pair of platens.

It is a further object of the invention to provide a press of this character in which both the stretching and clamping frames are pivotally attached to their respective platens, and have slidable engagement with a stationary part of the press frame, so that the stress placed upon each of these parts may be divided equally between two general lines of support.

It is another object of the invention to attach the stretching andclamping frames to their supporting platens at opposite ends of the press in such way as to avoid any interference of one frame carried on one platen with that carried on another.

The full nature of the invention, along with other objects and various features thereof, will be more fully understood from a consideration of the following description in the light of the accompanying drawings, in which Figures 1 and 1a show collectively a press having clamping and stretching frames pivotally attached to press platens at the opposite ends thereof;

Fig. 2 is a sectional view taken on the line 22 of Fig. 1;

Fig. 3 is a fragmentary plan view, looking downwardly upon the end portion of the press illustrated in Fig. 1;

Fig. 4 is a side' elevational view, on a reduced scale, showing a part of the stretching frame in a position comparable to that of Fig. 1;

Fig. 5 is a similar view of the clamping frame in the position shown in Fig. 1a; and

Fig. 6 is a perspective view of the clamping frame of Fig. 5.

In vulcanizing rubber impregnated belts, and treating similar relatively thin sheet-like articles, it is almost essential to stretch them at the same time that they are compressed and heated. For this purpose the article, and it will be assumed for purposes of the description that it is a belt of the type above mentioned, is placed between the 1937, Serial No. 170,792

platens of an appropriate press with one of its ends held in the jaws of a clamping frame and its other end between similar jaws of a stretching frame. The latter parts are capable of movement in a direction lengthwise of the platens so as to stretch the belt to a desired extent. Then, or simultaneously with the stretching, one'of the platens is moved towards the other, so as to subject the belt to the desired compressive force; and when that has been done the platens are heated to such degree and maintained in that condition for such time as is necessary to effect proper vulcanization.

The press for this type of work may take any desired form. The one illustrated in Figs. 1 and 1a is a somewhat large, cumbersome structure, quite long a compared with its width. Its manufacture is something of a custom job, and for that reason it is usually, although not necessarily, built up from a plurality of substantially identical units It) mounted in side by side relation upon an appropriate supporting bed, and each unit is tied to its adjacent one both at the top and at the bottom by one or more tiebolts ll.

Each unit, when constructed in the manner here shown, comprises a top crosshead l2, and a base crosshead l3, joined together at opposite sides by a pair of tension-rods M of circular or other desired configuration. When inter-connected by the tiebolts above mentioned, the top crossheads support an upper platen l5 either as an integral, or as a removable part; and the lower ones have cylinders I6 formed therein to which fluid may be admitted from any desired source under pressure so as to lift their pistons l9 and, either directly or through the intermediary of a follower element, the lower steam plate 20.

In view of the large and expensive character of the press it should, in the interests of economical operation, be so arranged as to be capable of pressing and stretching several belts simultaneously. That aim, however, is complicated by the fact that articles cannot satisfactorily be superposed directly one upon the other during vulcanization; nor is it ordinarily possible to control the size, etc., within prescribed limits of the articles when several of them are stretched in a common frame. To avoid these difficulties, intermediate steam platens 2|, of which one is shown, are interposed between the upper and lower ones so that several belts 22 may be accomodated simultaneously, one between each adjacent pair of platen surfaces; and a clamping frame 23, and a stretching frame 24, is attached to each of the lower and intermediate platens for engaging the end portions of the individual belts and applying a tensile force thereto.

Each clamping frame 23, as may best be seen in Figs. 1, 1a, 2 and 5, comprises a pair of side plates 25, each carrying a cylinder 26 on its upper end, and held in spaced relation by the tiebolts 21, and the upper and lower crossbeams 28 and 29, of which the upper, 28, is slidably mounted, and attached to the pistons carried in the cylinders 26, and the lower one, 29, is stationarily afiixed to the side plates with its upper face so disposed as to serve as an anvil against which an end of a belt may be clamped by the descending beam or jaw 28. Each side plate 25, in addition, carries an angle arm '30 having a bearing 3| formed in its outer end for pivotal connection to one of the platens, and a vertical slideway 32 for cooperation with a stationary 'part of the press frame, all as will be considered hereinafter.

The stretching frame 24, as may be seen by reference to Figs. 1, 2 and 4, comprises a .pair of spaced side piecesgenerally designated .33, of truss-like character, so as to withstand the strains imposed upon them, and each having horizontal ways 34 therein for the guidance and support of a longitudinally movable clamp member 35, a horizontal cylinder 36 having a piston and rod 31 connected at its outer end to the clamp 35 so as to move the latter in a horizontal direction; a journal bearing 38 for pivotal connection to one of the steam plates, and a vertical slideway 39 for cooperation with an appropriate roll carried on a stationary part of the press frame in a manner later to be described. The clamp 35, except insofar as it is slidably mounted in the ways34 as indicated at 4|] (Fig. 2), is generally similar to the clamping frame 23 hereinbefore described. Specifically, it comprises a pair of side plates 4|, each carrying a vertically disposed cylinder 42, and tied together by tiebolts =43; upper'and lower crossbeams 44 and 45, respectively, of which the upper one, 44, is slidably mounted in the side plates and attached to the pistons 46 in the cylinders 42, and the lower one, 45, is stationarily mounted so that its upper surface 41 serves as an anvil against which an end of the belt may be clamped by the descending jaw or beam 44.

The general construction of the clamping and stretching parts of the frames 23 and 24 are well known in the art and further description thereof is unnecessary.

Each of the lower and intermediate steam plates 20 and 2|, as hereinbefore mentioned, carries a stretching frame at one end, and a clamping frame at the other, and each of these frames is so arranged that the upper surface of its anvil lies in a continuation of the plane of the upper surface of its supporting platen. In order to prevent interference between the frames of one platen and those of another, both located at the same end of the press, and at the same time to be able to use standard frames of the type shown, the present invention provides a novel arrange- I ment in that the clamping and stretching frames for the intermediate steam plate 2| are just reversed in position as compared to the like parts of the lower steam platen 29. More specifically, and as shown by reference to Figs. 1 and 1a, the platen 20 carries a clamping frame 23 at its right-hand end, and a stretching frame 24 at its left end, while on the platen 2| the position of these parts is just reversed. Hence, as can be seen, the clamping frames 23 at each end of the press fit in the space between the ends of the platens and that occupied by the pistons and clamping parts of the stretching frames 24. To avoid interference between the lower crossbeam 29 of the clamping frame 23 attached to the lefthand end of platen 2|, with the belt disposed between the lower and intermediate platens, this beam must be relatively shallow-not a deep channel such as the one shown in Figs. 1a and 5. Similarly, the upper crossbeam of the clamping frame which is attached to the right-hand end of the lower platen 20 must be relatively shallow in order to prevent that part from interfering with the belt disposed between the intermediate and upper platens. When arranged and constructed in the manner shown, a pair of belts may be disposed between the adjacent surfaces of the three platens and individually stretched to a desired extent while they are simultaneously subjected to a desired compressive force.

In operation each of these various frames is subjected to very heavy stresses, and it is accordingly desirable that the .load upon them be divided-between two lines of support in the general manner described in Patent No. 2,090,377. Thus each frame, as has hereinbefore been, pointed out, has bearings 3|, for the clamping frame, and 38, for the stretching ones, adapted to engage appropriate journals carried on the lower and intermediate platens, and each is further provided with vertical slideways .32 and 39, respectively, for cooperation with stationary parts carried by the upper crossheads of the press frame. Specifically, and as may best be seen in Fig. 3, the upper steam platen l5, which is supported directly by the upper crossheads of the press frame, carries a bracket 48 at each of its corners, having a pair of journals 49 and 50; and each journal carries an ordinary caged anti-friction bearing, 5| and 52, respectively, on its end which engages the surfaces of the vertical slideways 32 and Y39 of the clamping and stretching frames 23 and 24, respectively. ,Accordingly, it may be seenthat each of the frames is pivotally attached to its platen and is relatively slidably engaged with a stationary part of the press frame by contact between its slideways and the bearings just described. Therefore the stress imposed upon each of these frames is divided between .twolines of support represented, respectively, by the lowerand intermediate platens 20 and "2|, and the upper platen and top crossheads of the press.

A'feature of this design not shown in the patent above identified, resides in the fact that the slideways make line contact with the outer races of the anti-friction bearing on the frame, and hence any slight misalignment of the various parts cannot result in a binding at this point.

In the press here shown and described the lower platen is both strong enough and stiff enough to be mounted upon the heads of the pistons so 'as to take the load directly; and sufliciently thick to accommodate the bosses upon which the clamping and stretching frames are pivotally mounted. There are presses, however, in which the platens are made of relatively thin rolled steel stock that has neither the stiffness nor thickness requisite for these purposes, and a piston crosshead or follower must then be provided. In such instances the clamping and stretching frames may be pivotally supported on bosses carried by this intervening element. The upper surfaceof the frame anvil'must still be aligned with the upper surface of the lower platen, of course, to carry out the aims-of the invention, and this may be done by arranging the bosses on the ends of Outriggers carried by the intervening element, or, more simply, by providing an angular arm on the frame which extends down for sufficient distance to engage bosses mounted directly on the intervening element, as shown in the above identified patent. Further, there are occasions when it is desirable to free the platen, regardless of its thickness or strength, from all external stress. Then the stretching and clamping frames may be supported on bosses carried by an intervening follower if one is provided, or by the pistons themselves if one is not. Here again, of course, it is essential that the surface of the frame anvils be aligned with the upper surface of the platen; and this may readily be done in the way above outlined.

It is not necessary to the present invention that the frames be supported directly by the lower platen for, as has been shown, the same results can be obtained by an indirect mounting. In any of the cases mentioned in the foregoing paragraph the frame or frames in question may be said to be pivotally associated with the lower platen, and where that term is used in the following claims it is to be understood to mean that the frame is pivotally mounted upon the lower platen or upon some part of the platen-moving means.

Since certain changes may be made in the construction without in any way departing from the teachings of the invention, it is intended that the foregoing shall be construed in a descriptive rather than in a limiting sense.

What I claim is:

1. The combination with a multiple belt press or the like comprising a frame having base and top crossheads joined by side members, a plurality of platens located in said frame including an upper, an intermediate and a lower one, and means for bringing said platens together to compress sheets of material disposed therebetween; of a clamping frame and a stretching frame pivotally connected respectively to the lower and intermediate platens and having relatively slidable engagement with the upper platen at one end of the press; and of substantially identical clamping and stretching frames pivotally connected respectively to the intermediate and lower platens and having relatively slidable engagement with the upper platen at the other end of the press.

2. The combination with a multiple belt press or the like according to claim 1 in which each of said clamping and stretching frames includes a fixed lower crossbeam and a vertically movable upper one, and in which said frames are pivotally connected to the platens at such points that the upper surfaces of their lower crossbeams lie substantially in a continuation of the planes of the upper surfaces of their respective platens.

3. The combination according to claim 1 further characterized in that each of the stretching frames comprises a pair of side pieces pivotally connected to its supporting platen and having vertically disposed ways engaging a relatively stationary part of the press fname, a clamping member slidably mounted in said side pieces for movement in a horizontal direction, and means for moving the clamping member; and wherein each of the clamping frames is pivotally attached to its respective supporting platen so as to lie between the side pieces of the adjacent stretching frame.

4. The combination according to claim 1 further characterized in-that each of the stretching frames comprises a pair of spaced side pieces having means for pivotally engaging the side edges of its supporting platen, vertically and horizontally disposed ways in each of said pieces, a clamping member disposed between said pieces and slidably supported in the horizontal ways thereof, a cylinder carried by each of the pieces, and a piston in each cylinder having connection with the clamping member for moving it in a horizontal direction; in that each of the clamping frames lies between the side pieces of the adjacent stretching frame and comprises a pair of spaced side plates having means for pivotally engaging the opposite sides of its supporting platen, and vertically disposed ways therein; and in that the upper platen carries a pair of roller bearings at each of its comers, for engaging the vertical ways of the stretching and clamping frames.

5. The combination with a multiple belt press or the like comprising a frame having base and ,top crossheads joined by side members, a plurality of platens located in said frame including an upper, an intermediate and a lower one, and means for bringing said platens together to compress sheets of material disposed therebetween, of a clamping frame and a stretching frame pivotally associated with the lower and intermediate platens respectively at one end of the press, and of similar clamping and stretching frames pivotally associated with the intermediate and lower platens, respectively, at the other end of the press, with all of said clamping and stretching frames having relatively slidable connection with a stationary part of the press frame.

6. The combination with a multiple belt press or the like according to claim 5 in which each of said clamping and stretching frames includes a fixed lower crossbeam and a vertically movable upper one, and in which said frames are pivotally connected at such points that the upper surfaces of their lower crossbeams lie substantially in a continuation of the planes of the upper surfaces of their respective platens.

'7. The combination according to claim 5 further characterized in that each of the stretching. frames comprises a pair. of side pieces pivotally connected to its supporting part and having vertically disposed ways engaging a relatively stationary part of the press frame, a clamping member slidably mounted in said side pieces for movement in a horizontal direction, and means for moving the clamping member; and wherein each of the clamping frames is pivotally attached to its respective supporting part so as to lie between the side pieces of the adjacent stretching frame.

8. The combination with a multiple belt press or the like comprising a frame, a plurality of platens located in said frame including an upper,

an intermediate. and a lower one, and means for moving said platens together to compress belting material therebetween; of a stretching frame comprising a pair of spaced side pieces each having pivotal connection with one of said platens, other than the upper one, at one end of the press, vertical ways in said side pieces, a clamping member slidably mounted in said side pieces. and means for moving said clamping member in horizontal direction; of a clamping frame disposed between the side pieces of the stretching frame and pivotally connected with another of said platens, other than the upper one, at the same end of the press; said clamping frames having vertical ways therein; of rollers carried on the upper platen for engaging the vertical Ways of the clamping and stretching frames; and of means located at the opposite ends of the press cooperating with said clamping and stretching frames for subjecting belting material or the like to tension while holding it in position to be compressed between the platens.

9. The combination with a press having a plurality of platens including an upper, an intermediate, and a lower one, and means for moving said platens together to compress sheets of belting material or the like disposed therebetween;

of a stretching frame attached to one of the I platens other than the upper one at one end of the press, and a clamping frame attached to another of the platens other than the upper one at the same end of the press, both said stretching and clamping frames being pivotally attached to their respective supporting platens and having relatively slidable engagement with a stationary part of the press; and of means located at the opposite end of the press cooperating with said frames in stretching belting materials or the like between said platens.

CARL F. SCHN'UCK. 

